35 johnson

[ReeseK]

can somebody explain how the intake and exhaust work on a boat motor? specificly what would keep the cyl pressure to high? if I remove the top cyl. spark plug the motor will turn over and fire well but with the top plug in the motor will barely turn over. I think my problem is with the intake considering the exhaust seems to have no valves.

 

[DHPMARINE]

Re: 35 johnson

This sounds like a battery problem,BUT what happens if you remove the bottom sparkplug?And do the same test?<br />DHP

 

[rolmops]

Re: 35 johnson

Go to : www.keveney.com <br />it will give you an animated show on the 2stroke and many other types of engines.

 

[rolmops]

Re: 35 johnson

sorry ,pressed the wrong button.

 

[JB]

Re: 35 johnson

I agree with DHPM.<br /><br />Your problem is in the starter electrical circuit.

 

[TLanglitz]

Re: 35 johnson

I recently worked over my 1958 35 hp super seahorse. I had the same thoughts that you posted when it was really slow cranking. I evenually decided I had a bad starter so I purchased another. That one did the same thing. My mistake was in using jumper cables from my car directly to the starter to try to crank the motor. It seems like this would give it enough juice, but it doesn't. When I put the battery out of that car into the boat, the motor cranked like crazy. The first thing you should do is check the battery and the cables. Any problems there will cut amperage and cause the motor to do exactly what you are saying. By the way ... On my motor, the slow cranking actually lowered compression drastically.

 

[Stumpys]

Re: 35 johnson

Amazing what those little starters will draw on current, so I have have to agree with the above. All starters need a direct path from the battery with cables attached, and clean connections. Do not try and use jumper cables alone cause you get a huge voltage drop with the length of the cables and the poor connection. As voltage drops, current will go up. This will cause your starter to overheat, burn the commutator and brushes, short the field coil, and cause ya to have to buy a new starter. <br /><br />Make sure the battery is fully charged with clean and tight connections. If it is still slow, then ya have to ask the OB gurus.

 

[ReeseK]

Re: 35 johnson

I will do just that I have another battery I can try. I have a pull start I guess I could also try that! I reviewed the 2 stroke does each cyl. have an intake valve or do they share the same one?

 

[ReeseK]

Re: 35 johnson

tried a new battery did not help but I got it started with the pull start guess I will be needen a new starter. thanks